Rotatable brush for cleaning apparatus

ABSTRACT

A rotatable brush for cleaning apparatus is composed of a shaft supported for rotation within the apparatus. Attached to the shaft are a plurality of rows of bristles extending along the shaft in radially spaced relationship. The bristles are inclined relative to the axis of the shaft to permit maximum bristle length without increasing the overall diametrical dimension of the brush.

United States Patent 1191 Liebscher 1451 Aug. 13, 1974 [5 ROTATABLEBRUSH FOR CLEANING 271,971 2/1883 Batchelder 15/179 APPARATUS 395,3621/1889 Spangenberg 15/179 X [75] Inventor: Johannes Liebscher, NassauLahn, FOREIGN PATENTS OR APPLICATIONS Germany 409,860 5/1934 GreatBritain 15/179 [73] Assignee: Leifheil International Gunter 522Nassau/Lam Primary Examiner-Peter Feldman y Attorney, Agent, orFirmMichael S. Striker [22] Filed: July 13, '1971 21 A l. N 162,207 1 pp0 57 ABSTRACT [30] Foreign Application Priority Data A rotatable brushfor cleaning apparatus is composed July 28, 1970 Germany 7028262 of aShaft Supported for rotation Within the pp Attached to the shaft are aplurality of rows of bristles 52 US. Cl. 15/182, 15/41 extending alongthe Shaft in radially spaced relation- 51 1111.01. A46b 7/10, A46b 1/00P- The bristles are inclined relative to the axis of [58] Field ofSearch 15/179-1s3', the shaft to Pet/mit maximum bristle length Without5/198 200 4l 50 79 creasing the overall diametrical dimension of thebrush.

[56] References Cited UNITED STATES PATENTS 6 3 Draw F'gms 23,526 4/1859Edson 15/179 X v, /7 y W V", A .w, w.

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ROTATABLE BRUSH FOR CLEANING APPARATUS BACKGROUND OF THE INVENTION Thepresent invention relates in general to a rotatable brush for cleaningapparatus and more particularly to a rotatable brush for carpetcleaners.

It is known in cleaning apparatuses including a rotatable brush toarrange the bristles of the brush along the body of the brush shaftwhich is rotatable in the cleaning apparatus. In this type of rotatablebrush it is particularly important to maintain a maximum length of thebristles without sacrificing the bending capability of the bristles. Itis also important to maintain a sufficient bending resistance while atthe same time keeping the bristles soft enough for maximum cleaningeffect and to prevent mechanical destruction of the bristles or damageto textile floor coverings such as carpets. In known brushes, thisrequirement results in undesirable large overall diameters of the brushbody and consequent increase in overall structural dimension of thecleaning apparatus which, of course, is undesirable.

Accordingly, it is the primary object of the present invention toprovide a rotatable brush of the above type for cleaning apparatusparticularly carpet cleaning apparatus which permits reduction inoverall structural dimensions of the cleaning apparatus, while at thesam time permitting optimum bristle length. I

SUMMARY OF THE INVENTION In the present invention the above object isaccomplished by having the bristles arranged along the rotatable brushshaft in inclined position relative to the axis of the brush shaft. Inthis manner the relative stiffness of the brush along the entire lengthof the brush shaft can be varied within a wide range without increasingthe overall diameter of the brush.

ln known practice the bristles of the brush are normally arranged inrows of individual bunches of bristles which are attached to therotatable shaft body of the brush for radial extension therefrom.

The tips of all the bristles at opposite ends of the brush shaft arepreferably located in planes parallel to the axis of the shaft. By this,a substantially sturdy structure of the brush is obtained while at thesame time assuring simultaneous floor contact of all of the bristlesalong the shaft.

In accordance with the present invention it is proposed that alternaterows of bristles along the rotatable shaft be inclined in oppositedirections relative to the axis of the shaft and to each other toprevent possible side thrust by movement of the cleaning apparatus alongthe floor, particularly in the instance of lightweight cleaningapparatus, which otherwise would occur if the bristles were all inclinedin the same direction. By arranging the bristles of adjacent rows inopposite inclined directions as disclosed herein, thrust forces intransverse direction to the movement of the cleaning apparatus will beself-eliminating. By practical experiment an angle of inclination of thebristles of the brush from between 40 to 80 has been found to be bestsuitable. The preferred angle of inclination is about 60 which has beenfound to be best suited to ob tain maximum cleaning effect without anyundue harm to the bristles or the floor covering.

Furthermore, in accordance with the present invention, the bristles ofthe present improved rotatable brush can be selectively arranged in rowsparallel to the axis of the brush shaft or they may be arranged on theshaft along sinusoidal or helical paths.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a bottom view of arepresentative cleaning apparatus of the type herein referred to,incorporating one embodiment of an improved rotatable brush inaccordance with the present invention;

FIG. 2 illustrates another embodiment of a rotatable brush for thecleaning apparatus shown in FIG. 1; and

FIG. 3 is still another embodiment of a rotatable brush for thecleaningapparatus shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION With reference to the drawing andparticularly FIG. 1, there is illustrated a representative cleaningapparatus generally indicated at 10, such as a carpet cleaner, seen fromthe bottom thereof. The carpet cleaner 10, as will be understood, isonly representative of the type of cleaning apparatus in which theimproved rotatable brush of the present invention may be embodied. Itwill be further understood that the cleaning apparatus 10 may beequipped with a plurality of rotatable brushes 11 in any suitable knownarrangement including such arrangement in which the bristles of adjacentbrushes intermeshingly engage each other. The structure of the cleaningapparatus per se is considered to be irrelevant and forms no part of thepresent invention.

The schematically illustrated cleaning apparatus 10 is comprised of ahousing 12 which is equipped inwardly of the thereof with oppositebearing support members 13. Bearing support members 13, in thisinstance, each rotatably support a pair of ground contact wheels 14 andin between them a rotatable brush 11 which is the primary subject of thepresent invention.

In known cleaning apparatus of this type in order to vary the height ofthe rotatable brush 11 relative to the floor surface either bearings 15for the brush II or bearings 16 for the ground engaging wheels 14 may beadjustably supported on bearing support members 13. On the other hand,if no adjustment is required, all of the bearings may be stationary.

The rotatable brush 11 of the cleaning apparatus is comprised of a rigidrotatable brush shaft 17 which in the present instance is provided atboth ends with axial bearing recesses 18 adapted to engage bearingmembers l5 projecting from the main bearing supports 13. Both ends ofthe brush shaft 17 in this instance provide increased diameter headportions 19 which are each disposed between a pair of ground engagingwheels 14 at each side of the cleaning apparatus 10 and in drivingcontact with the wheels. Thus, during rotation of the ground engagingwheels 14 by movement of the cleaning apparatus across the floor surfacebrush 11 will be caused to rotate.

In the illustrated example of FIG. 1, the dirt and other contaminantspicked up by the rotating brush 11 will normally be deposited in shallowcontainers adjacent both sides of the brush ll. Containers 20 havemovable flaps 21 for convenient removal of the dirt from the containers20.

As illustrated in the embodiment of FIG. 1, the bristles 22 of brush 11are arranged in a plurality of individual packs or bunches as is known.A plurality of bristle bunches are disposed along the brush shaft 17substantially along the entire length thereof and in parallel rows 23,24 circumferentially spaced from each other. In the embodiment of FIG. 1the bristle rows 23, 24 as will be noted are disposed parallel to theaxis of the brush shaft 17.

In order to maintain a minimum floor clearance between the brush 11 andthe floor surface while at the same time maintaining the structuraldimension of the cleaning apparatus as small as possible and to providerelative soft floor contact of the bristles 22, the bristles 22 in anyone of the bristles rows 23, 24 are inclined at an angle less than 90and in the same direction relative to this axis of the brush shaft 17.By this arrangement the effective length of the bristles can beadvantageously increased in contrast to the arrangement in knownrotatable brushes which have radially extending bristles. By suitablevariation of the angle of inclination of the bristles any desirableeffective length of the bristles can be selected for optimum cleaningeffect while maintaining good bending characteristics of the bristlesand thereby a relatively soft floor contact in accordance with theparticular specific stiffness characteristic of the bristles.

In cleaning apparatus of particularly light-weight construction it is offurther advantage to arrange the rows of bristles 23, 24 such thatalternate rows are inclined in opposite directions relative to eachother. By this arrangement possible side thrust forces against therotating brush 11 will be effectively prevented since the occurringthrust forces of adjacent rows of bristles oppose each other.

It shall be mentioned here that any suitable number of rows of bristles23, 24 may be arranged around the brush shaft 17 in accordance with thediameter of the brush shaft 17 and the size of the cleaning apparatus10. However, an even number of rows of bristles is desirable for thereasons stated in the above.

In the embodiment of FIG. 2 the rotatable brush 25 is similarly composedof a substantially rigid brush shaft 17 having enlarged head portions 19at both ends thereof. The bristles 22 of brush 25 are similarly groupedin individual bunches, as is customary, and which in this instance arearranged in parallel rows extending along sinusoidal paths from end toend of brush shaft 17.

The individual sinusoidally arranged rows 26, 27 of bristles 22 areparallel to each other and bristles 22 are similarly inclined inlongitudinal direction at an angle less than 90 relative to the axis ofthe brush shaft 17. Here, likewise, the bristles of alternate rows ofbristles may be inclined in opposite direction relative to each other toeffectively counterbalance side thrust forces during rotation of thebrush 25 over the floor surface.

In the embodiment of FIG. 3, the rotating brush 29 is similarlyconstructed of a shaft 17 supporting a plurality of parallel rows ofbristles 30, 31. In this instance, the rows of bristles 30, 31 aredisposed in spiral or helical fashion along the brush shaft 17 parallelto each other. Similarly, the bristles 22 of alternate rows 30, 31 areinclined in opposite directions relative to the axis of the brush shaft17.

It will be obvious from the foregoing that the rows of bristles may bearranged in different manners than those illustrated and described,consideration only to be given to the fact that an even number of rowsbe employed so that always even numbers of rows of bristles are inclinedin opposite directions to each other. Furthermore, it has been found tobe of advantage to select the length of the bristles such that the tipsat the ends of each row of bristles are located in a plane parallel tothe axis of the rotatable brush shaft 17 to assure even ground contactof all of the bristles along the brush.

Preferably, and as determined by respective experiments, the angle ofinclination of bristles 22 relative to the axis of the brush shaft 17lies between 40 and whereby a mean of 60 inclination has been found tobe of particular advantage.

As previously mentioned, the illustrated embodiments represent onlyparticular examples of the invention which, however, is not limited tothese embodiments.

The invention readily lends itself to various modifications in detailand structure including brush shafts made of plastic material or anydesirable metal. The rotatable brush may also be made of wire forvariations in diameter and flexibility of the brush shaft. Obviously,the bearing arrangements and driving mechanism for the present improvedrotatable brush are subject to similar modifications, although thesearrangements form no part of the present invention.

As likewise mentioned before, the bristles of the brush of the presentinvention may be arranged on the brush shaft in other linear formsdifferent from those shown and described herein or the bristles may bearranged along the brush shaft 17 at random without following anyparticular linear or curvilinear pattern. Additionally, individualbunches of bristles may be of different lengths as required for certainparticular applications.

It will be understood that each of the elements described above inrelation to the present improved rotatable brush construction may alsofind useful applications in other types of cleaning apparatusesdiffering from the types described herein.

Thus, while the invention has been illustrated and described as embodiedin a known carpet cleaning apparatus, the invention is not intended tobe limited to the details shown, since various modifications andstructural changes may be made without departing in any way from thespirit and characteristic of the present invention.

Without further analysis the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be secured by Letters Patent isset forth in the appended claims:

1. A rotatable brush for cleaning apparatus, particularly for carpetsweepers, comprising an elongated rotary member; and tufts of bristlesprojecting from said member and being arranged in a plurality of rowshaving a substantially sinusoidal configuration, all of said rowsextending in substantial parallelism with one another, and the tufts ineach of said rows being free of contact with the tufts in therespectively adjacent rows, each of said bristles being inclined to theaxis of said member at an angle different from 90, and the bristles inadjacent ones of said rows being inclined in mutually oppositedirections.

' 2. A rotatable brush as defined in claim 1, each of said tufts havinga free end; and wherein the free ends of the tufts in each of therespective rows are located in a common plane substantially parallel tosaid axis.

3. A rotatable brush as defined in claim 1, wherein said angle issubstantially 40 to 4. A rotatable brush as defined in claim 3, whereinsaid angle is substantially 60.

5. A rotatable brush as defined in claim 1, wherein said rows extend ina direction along said axis.

6. A rotatable brush as defined in claim 1, wherein at least some ofsaid bristles are inclined in longitudinal direction of the respectiverow.

1. A rotatable brush for cleaning apparatus, particularly for carpetsweepers, comprising an elongated rotary member; and tufts of bristlesprojecting from said member and being arranged in a plurality of rowshaving a substantially sinusoidal configuration, all of said rowsextending in substantial parallelism with one another, and the tufts ineach of said rows being free of contact with the tufts in therespectively adjacent rows, each of said bristles being inclined to theaxis of said member at an angle different from 90*, and the bristles inadjacent ones of said rows being inclined in mutually oppositedirections.
 2. A rotatable brush as defined in claim 1, each of saidtufts having a free end; and wherein the free ends of the tufts in eachof the respective rows are located in a common plane substantiallyparallel to said axis.
 3. A rotatable brush as defined in claim 1,wherein said angle is substantially 40* to 80*.
 4. A rotatable brush asdefined in claim 3, wherein said angle is substantially 60*.
 5. Arotatable brush as defined in claim 1, wherein said rows extend in adirection along said axis.
 6. A rotatable brush as defined in claim 1,wherein at least some of said bristles are inclined in longitudinaldirection of the respective row.